28901985 has 32 divisors (see below), whose sum is σ = 53057280. Its totient is φ = 13160448.

The previous prime is 28901981. The next prime is 28901987. The reversal of 28901985 is 58910982.

It is a happy number.

It is not a de Polignac number, because 28901985 - 2² = 28901981 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28901981) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42609 + ... + 43281.

It is an arithmetic number, because the mean of its divisors is an integer number (1658040).

Almost surely, 2^28901985 is an apocalyptic number.

It is an amenable number.

28901985 is a deficient number, since it is larger than the sum of its proper divisors (24155295).

28901985 is a wasteful number, since it uses less digits than its factorization.

28901985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097.

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 28901985 is about 5376.0566403266. The cubic root of 28901985 is about 306.8851618427.

The spelling of 28901985 in words is "twenty-eight million, nine hundred one thousand, nine hundred eighty-five".